Windows build 2.4-git (Dec 4)/KDE 4.5.4: Cannot select media source?

[Don Levey]

I've just installed the Windows build 2.4-git (December 4) on my machine
running WinXP (work machine).  While I can use the Playlist menu to
browse for and select media to play, I find I cannot select a media
source in the "Media Sources" pane on the main canvas, as I can on my
Fedora machine at home.  I've tried each button with no success; this is
after a full scan of my media directories.  Have I missed something?
I'm not seeing any related topic mentioned on the website forum.

Thanks in advance for any help,
 -Don Levey